<html>
 
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>系统时间</title>
</head>
 
<body>
    <script>
        Date.prototype.format = function (fmt) {
            var o = {
                "y+": this.getFullYear, //年
                "M+": this.getMonth() + 1, //月份
                "d+": this.getDate(), //日
                "h+": this.getHours(), //小时
                "m+": this.getMinutes(), //分
                "s+": this.getSeconds() //秒
            };
            if (/(y+)/.test(fmt)) fmt = fmt.replace(RegExp.$1, (this.getFullYear() + "").substr(4 - RegExp.$1.length));
            for (var k in o)
                if (new RegExp("(" + k + ")").test(fmt)) fmt = fmt.replace(RegExp.$1, (RegExp.$1.length == 1) ? (o[k]) : (("00" + o[k]).substr(("" + o[k]).length)));
            return fmt;
        }
        setInterval("document.getElementById('dateTime').innerHTML = (new Date()).format('yyyy-MM-dd hh:mm:ss');", 1000);
    </script>
 
    <div id="dateTime"></div>
</body>